This invention is an improved machine for cutting index notches in books, magazines, catalogs, and other reading or reference material.
Index notches offer advantages over other methods of marking book sections or pages. These marking methods include protruding tabs and leaf-edge marking techniques. Protruding tabs can be easily torn or tear the leaf they are attached to. They are unsightly and can be squashed flat when the book is placed in a shelf. In the leaf-edge marking technique, typically all the leaves in the section to be marked are printed with a contrasting band along their fore-edge, extending beyond the position where the leaf edge is to be sheared. This method adds no extra steps to book manufacture, but cannot convey any printed information such as the name or number of the section, the letter of the alphabet (as in a dictionary), or the like.
An improved leaf edge marking technique uses short stripes printed on the fore-edges of all leaves in a section of the book. There is also a contents page, typically just inside the front cover, on which each section title is positioned vertically to correspond to the vertical position of that section's fore-edge stripes. This method is superior in convenience to other prior art for non-alphabetic reference books, but is found in only a small fraction of the books where it would be useful. It must be included in the book when it is manufactured, and cannot be easily put in by the book user, or customized to the user.
In the prior art of index notches, they are used almost exclusively in alphabetically ordered books such as dictionaries. In such volumes, the notches typically show only one or two letters, allowing the user to quickly turn to the beginning of the "M" section, for example.
This use of notches, although very common, is of limited value because once the user has reached the first page of the M's, he or she still has several iterations to do on subsequent letters of the target word before the desired page is reached. Thus an alphabetic notch helps with only the first of several steps. In addition, knowing the alphabet, one can usually get close to the desired first letter even without notches, simply by guessing its position. For example, the M's would be found near the middle of a dictionary or telephone directory.
Notches also substantially increase the cost of production of a book. In spite of their disadvantages, notches are still popular, because any gain in efficiency of use is valuable in a reference book.
There is also much printed reference material which is not organized alphabetically, including most catalogs, textbooks, law books, medical texts, technical reference material, repair manuals, contractor's specifications, history books, etc. In these the order of material is frequently logical, chronological arranged by subject, etc.
For example, a user of a computer reference book on a spreadsheet program may need to refer frequently to the section on graphs, or on macros. Or, a user of an industrial hardware catalog may need to turn frequently to the section on flat-head screws. It would be useful if such a user could make a notch which lead him or her immediately to the desired section. This lets the user avoid several steps: finding the index, looking up the desired item in it, and turning to the correct page. Such a set of notches would serve as a short, customized table of contents.
For this use, the notch would have to be big enough to show a label typically comprising a few words, rather than just a letter or two. Therefore notches for use in non-alphabetic material should be larger than typical notches found in dictionaries, for example.
There is also much reference material published without notches, usually for reasons of cost. Use of many of these, for example telephone directories, would benefit from simple alphabetic notches, just as dictionaries do. Much of this reference material is printed with narrow margins, also for reasons of cost. A truly versatile notch cutter should therefore be able to cut shallow notches or large ones.